Even small amounts of red and processed meat - such as a rasher of bacon a day - can increase the risk of bowel cancer, according to research.
The latest study led by Oxford University and funded by Cancer Research UK, adds to the evidence, including from the World Health Organization, that eating red meat can be harmful.
But exactly how big is the risk? And how much is too much?
Here's what you need to know.
Researchers analyzed data from almost half a million people involved in the UK Biobank study.
Over the six years of their study, they found 2,609 people developed bowel cancer.
They estimate:
- Eating three rashers of bacon a day rather than just one could increase the risk of bowel cancer by 20%
- For every 10,000 people in the study who ate 21g a day of red and processed meat 40 were diagnosed with bowel cancer
- The comparable figure for those who ate 76g a day was 48
According to the NHS, 76g of cooked red meat is equivalent to about half an 8oz sirloin steak. A slice of ham or rasher of bacon is about 23g of processed meat.
It's not clear. Cancer Research UK says 5,400 of the 41,804 cases of bowel cancer seen each year in the UK could be prevented if people did not eat processed meat at all.